Dwarf Indigobush, Dwarf false indigo, Dwarf Indigo
Amorpha nana
Family: Fabaceae or Leguminosae
What it is like
Bloom Color: Lavender, Purple. Main Bloom Time: Early summer, Late spring, Mid summer. Form: Prostrate, Spreading or horizontal.
Amorpha nana is a deciduous Shrub growing to 0.6 m (2ft) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 4. It is in flower from July to August. The species is hermaphrodite (has both male and female organs). It can fix Nitrogen. Suitable for: light (sandy) and medium (loamy) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers dry or moist soil and can tolerate drought.
Height (m): 0.6
Where it is found
Dry prairies in S. Manitoba.
Western N. America - Minnesota to the Rocky Mountains.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 1
The plant has been used as a snuff in the treatment of catarrh.
Expectorant: Clears phlegm from the chest by inducing coughing.
Other
Rating: 2
The resinous pustules on some species yield the insecticide 'amorpha'. The plant has a strong spreading root system and this makes it useful for controlling soil erosion.
Insecticide: Kills insects.
Soil stabilization: Plants that can be grown in places such as sand dunes in order to prevent erosion by wind, water or other agents.
Food Forest: Plants for Edible Forest Gardens and Food Forests.
Nitrogen Fixer: Plants that fix nitrogen in the soil
How it is grown
Landscape Uses:Erosion control. Prefers a light well-drained sandy soil in sun or light shade. Fairly wind-resistant. A very hardy plant, tolerating temperatures down to about -25c. Plants resent root disturbance, they should be planted out into their final positions whilst small. Plants are said to be immune to insect pests. Flowers are produced on the current season's growth. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. Special Features:Invasive, Naturalizing, Attractive flowers or blooms. For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is multistemmed with multiple stems from the crown.
Propagating it: Seed - presoak for 12 hours in warm water and sow early spring in a greenhouse. The seed usually germinates in 1 - 2 months at 20°c. When large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out in late spring or early summer, after the last expected frosts. Cuttings of half-ripe wood, June/July in a frame. High percentage. Cuttings of mature wood of the current seasons growth, autumn, in a sheltered position outdoors. Takes 12 months. Suckers in spring just before new growth begins. Layering in spring .
Best place to grow: Cultivated Beds;
Habit: Shrub
Hardiness: 4-8
Growth: Medium
Soil: Light (sandy), medium
Shade: Semi-shade, no shade
Moisture: Dry, moist
Things to keep in mind
Its other names
Local names
Synonyms
A. microphylla.